<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8">
    <title></title>
  </head>
  <style>
    div{
      width: 200px;
      height:200px;
      margin: 200px auto;
      background: #ccc;
    }
    .box{
      transition: width 1s ease-in-out,height 2s ease-in-out 1s;
    }
    .box:hover{
      width:400px;
      height:400px;
    }
  </style>
  <body>
    <div class="box">
      123
    </div>
  </body>
</html>
